1. Field of the Disclosure
The present disclosure relates to electronic devices, more particularly, to electronic devices that include semiconductor fins having a plurality of gate electrodes and processes for forming them.
2. Description of the Related Art
Electronic devices, including a fin-type component having a first gate electrode along a first side and a second gate electrode along a second side of a semiconductor fin, can be difficult to manufacture. One attempt is to form separate first and second masking members with a gap between them prior to etching a gate electrode layer. However, the width of the fin, the distance from the first side of the semiconductor fin to the second side of the semiconductor fin can be close to the limit of the lithography process. Consistently resolving a gap on top of the semiconductor fin at substantially minimum spacing for the lithography process can be difficult to accomplish.
Another attempt is to form a single conductive member that overlies the fin-type structure, and later separate the single conductive member into two gate electrodes using an additional masking layer and separation etch process. However, performing such a process has overlay issues because one masking layer is required to form the conductive member over the semiconductor fin, and a second masking layer is required to protect the gate electrode portions of the conductive member during the separation etch process. Additional masking layers add complexity and expense to the process.
The conductive member can also be separated by chemical mechanical planarization to avoid performing the additional masking operation. However, chemical mechanical planarization has a global effect, so all gate members at the same elevation will separate at substantially the same time. Integration of chemical mechanical planarization is also difficult and expensive if dual gate and single gate components are to be integrated within a single electronic device.
Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the invention. The use of the same reference symbols in different drawings indicates similar or identical items.